During the drilling, work over, or plug and abandonment of oil and gas producing wellbores, a variety of down hole tools may be attached to a pipe or coiled tubing string and utilized to perform various functions within the wellbore. Circumstances arise making it desirable to bypass flow around the downhole tool string within the wellbore. These circumstances can include lost circulation, well control, the need for an increased pump rate, and others of the like which require the flow of fluid within the pipe string to be bypassed around the tool string.
Current cyclical bypass valve devices employ a deformable ball to activate the bypass valve, allowing fluid to travel around the tool string and within the wellbore. A second, metal ball(s) is employed to close the bypass valve off and allow circulation to continue through the tool string. Pumping a ball through a pipe or coiled tubing string is a very time consuming process, especially through a coiled tubing string where the ball must travel through the entire spool of coiled tubing before it even reaches the vertical column within the wellbore.
Consequently, there is a need for a pressure activated cyclical valve apparatus which employs only a single ball to both activate and deactivate the bypass valve configured within the apparatus.